Embodiments relate to a method for manufacturing a semiconductor device.
A metal line of a semiconductor substrate may connect circuits formed in a semiconductor substrate to each other, for example through electrical connections between semiconductor devices and a pad connection. Such connection may be performed using a metal thin film such as aluminum, alloy thereof, or copper.
To connect a device electrode and a pad isolated by an insulating layer such as an oxide layer, the insulating layer may be selectively etched to form a contact hole. A metal plug to fill the contact hole may be formed, for example using a barrier metal and tungsten. Next, a metal thin film may be formed and patterned at an upper portion of the metal plug to form a metal line for connecting a device electrode and a pad to each other.
A photolithography process may be performed to pattern the aforementioned metal line. As semiconductor devices have become smaller, however, a critical dimension (CD) of the metal line has been reduced. Accordingly, it may be difficult to form a fine pattern of the metal line. Hence, a damascene process has been developed to more easily form a metal line having a fine pattern.
To make a metal line through a damascene process according to the related art, however, two (2) photolithography processes, three (3) etch processes, and two or three (2-3) ashing processes may be required.
Accordingly, the time required to fabricate a product may be lengthy, and may result in an increased cost. In addition, excess material may remain between processes, and that may deteriorate the reliability of a resulting semiconductor device.